The purpose of the present invention is to provide an actuator that has a simple configuration and can stably achieve high output without the occurrence of magnetic saturation. This actuator has: a movable body provided with a cylindrical magnet section having alternately N-pole faces and S-pole faces on the peripheral surface surrounding a rotation shaft; and a fixed body provided with, pole tooth surfaces of the same number as the N-pole faces and the S-pole faces, and a coil that excites the pole tooth sections. The movable body has as a turning reference position a position at which the center of the pole tooth surfaces in the circumferential direction and the switching position of the pole faces of the magnet section face each other, and is held to the fixed body so as to be turnable back and forth around the rotation shaft in the circumferential direction.